Question

Someone please help me!

Answer 1

For this case what you should do is evaluate values of x in the function and verify that they meet the result of f (x) shown in the graph.
 The answer is
 f (x) = - 2lxl +1
 notice that
 f (1) = - 2l1l + 1 = -1
 f (-1) = - 2l-1l + 1 = -1
 Both comply with the value of f (x) shown in the graph
 answer
 f (x) = - 2lxl +1